1. Field of the Invention
The present invention relates generally to scroll-type compressors. In particular, the invention is directed to scroll-type compressors in which particular elements of the compressor are lubricated without using a gasket.
2. Description of Related Art
Known scroll-type compressors, such as the compressor described in Japanese Patent (Unexamined) Patent Publication No. H11-82335, include a housing, and the housing includes a front housing, a shell, and a rear housing. Such known compressor also include a fixed scroll-including a first spiral element, and an orbiting scroll including a second spiral element. The spiral elements interfit with one another to form a sealed-off fluid pocket. Such known compressors further include a driving mechanism which drives the orbiting scroll in an orbiting motion, and a rotation preventing mechanism which prevents the orbiting a scroll from rotating. The orbiting scroll, the fixed scroll, the driving mechanism, and the rotation preventing mechanism are positioned inside the housing. Further, such known compressors also include a suction chamber and a discharge chamber, and the fixed scroll separates the suction chamber from the discharge chamber. The driving mechanism and the rotation preventing mechanism are positioned inside the suction chamber. Moreover, a communication path is formed through the fixed scroll, and a gasket is inserted between the fixed scroll and the rear housing to allow fluid communication between a lower portion of the discharge chamber and an upper portion of the suction chamber.
In the known compressor, a refrigerant gas is introduced into the suction chamber via an external refrigerant circuit. Moreover, a lubricating oil suspended in the refrigerant gas lubricates the driving mechanism, the rotation preventing mechanism, and sliding portions located between the fixed scroll and the orbiting scroll. Specifically, during operation, the lubricating oil separates from the refrigerant gas, and accumulates in a lower portion of the discharge chamber. This accumulated lubricating oil flows to an upper portion of the suction chamber via the communication path, when a pressure in the discharge chamber is greater than a pressure in the suction chamber, and subsequently flows from the upper portion of the suction chamber to a lower portion of the suction chamber. When the lubricating oil flows from the upper portion of the suction chamber to the lower portion of the suction chamber, the lubricating oil lubricates the driving mechanism, the rotation preventing mechanism, and the sliding portions located between the fixed scroll and the orbiting scroll. Moreover, when the refrigerant gas is discharged into an external refrigerant circuit via the discharge chamber, the discharged refrigerant does not include the lubricating oil because the lubricating oil previously was separated from the refrigerant gas. Therefore, efficiency of the external refrigerant circuit may increase. Nevertheless, in such known compressors, the gasket is used to lubricate the driving mechanism, the rotation preventing mechanism, and the sliding portions located between the fixed scroll and the orbiting scroll. Consequently, the size of the known compressor, and the cost of manufacturing the known compressor, increases.
Therefore, a need has arisen for scroll-type compressors which overcome these and other shortcomings of the related art. A technical advantage of the present invention is that particular elements of the compressor are lubricated without using a gasket.
According to an embodiment of the present invention, a scroll-type compressor comprises a housing comprising a suction chamber and a discharge chamber. The compressor also comprises a fixed scroll comprising a first spiral element. Specifically, the fixed scroll is fixed to the housing, and a sealing member seals the fixed scroll and the housing. The compressor further comprises an orbiting scroll comprising a second spiral element. Specifically, the orbiting scroll is positioned inside the suction chamber, and the first spiral element and the second spiral element interfit with each other to form a fluid pocket. Fluid is compressed within the fluid pocket during operation of the compressor. Moreover, the compressor comprises a driving mechanism to move the orbiting scroll in an orbiting motion, a rotation prevention mechanism to prevent the orbiting scroll from rotating, and a first circumferential groove formed at a circumferential surface of the fixed scroll. The compressor also comprises a second circumferential groove formed at a bottom surface of the first circumferential groove, and the sealing member closes an open end of the second circumferential groove, such that a first communication path is formed through the second circumferential groove. The compressor further comprises a second communication path formed at a lower portion of the fixed scroll. Specifically, the second communication path allows fluid communication between a lower portion of the discharge chamber and a lower portion of the first communication path. Moreover, the compressor comprises a third communication path formed at an upper portion of the fixed scroll. Specifically, the third communication path allows fluid communication between an upper portion of the suction chamber and an upper portion of the first communication path.
Other objects, features, and advantages will be apparent to persons of ordinary skill in the art from the following detailed description of the invention and the accompanying drawings.